Pneumatic tire



. Imeni'/ Lau/@now CWI/'lla L. C. MILLS PNEUMATIC TIRE Filed June 2,` 1932 Aug. 25, 1936..

Patented Aug. 25, 1936 OFFICE PNEUMATIC TIRE Lawrence C. Mills, Chicago, Ill.

Application June 2, 1932, Serial No. 614,906

v1 claim.

My invention relates to pneumatic tires for vehicles, and has particular reference to a tire provided with two inner tubes so that upon the deflation of one tube, the othertube willcarry the load without the necessity of immediate attention.

' An important object of the present invention resides in the provision of a tire having a novel integral inner partition means defining separate compartments for the-inner tubes.

Another objectzis to provide a partition means of the foregoing character which will not interfere with the normal shape and resiliency of the tire, which is simple and inexpensive in construction, reliable andefflcient in use and not likely to crimp or in any way injure the inner tubes, and which readily permits removal or insertion of the inner tubes.

Further objects and advantages will become apparent as the description proceeds.

In the accompanying drawing, Figure 1 is'a transverse sectional view of an inated tire embodying the features of my invention.

Fig. 2 is a view similar to Fig. 1 but showing the tire with one of the inner tubes deflated.

Fig. 3 is a somewhat diagrammatlctransverse sectional view of the fabric portion of the tire.

Fig. 4 is a fragmentary detail view of the paro titill.

Fig. 5 is a side view on a reduced scale of the tire and wheel assembly.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawing and will herein describe in detail the preferred embodiment, but

it is to be4 understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modiiications and alternative constructions falling within -the spirit and scope of the invention as expressed in the appended claim.

Referring more particularly to the drawing, the tire constituting the preferred embodiment of the invention comprises in general an outer ,casing Ill of standard construction having an outer peripheral tread wall II and side walls I2 terminating in peripheral beads I3 adapted to seat' on the usual wheel rim I4.

Formed integral with the casing III centrally of the tread wall II and. normally extending diametrically through the interior thereof is a vertical annular partition wall I5 forming two lateral compartments I6 and I1. 'Iwoinner tubes I8 and I9 provided respectively with suitable valve fittings 20 and 2| are inserted respectively (ci. 1524-22) o in the compartments I6 and I1, and bear against opposite sides of the partition wallIS.

The inner peripheral edge of the partition wall I5 is formed integral with two oppositely extending flaps 22 and 23k which are adapted to lie 5 against the side walls'IZ and particularly to close the peripheral opening between the beads I3.

The flaps 22 and 23 are long and gradually tapered in order to afford a smooth interior not likely to pinch or crimp the inner tubes I8 and l0 I9 and to provide a reenforcing covering sub-I stantially enveloping the inner portions of the tubes. Thus, the iiaps each extend through approximately one-fourth of the transverse circumference of the casing I0.

The aps 22 and 23 and the partition wall I5 also are thin and flexible so that the normal shape and resiliency of the tire when inated will not be impaired and that in the event of one inner tube becoming deated, the wall will yield readily 20 to the expansion of the remaining tube. I

The partition wall I5 may be made of any suitable yieldable or flexible material. In the present instance. it consists of four plies of rubber impregnated fabric. Preferably, the two in- 25 ner plies of cord fabric forming the side walls I2 of the casing III meet and are joined at the centerof the tread wall II to form the four ply partition wall. At the inner peripheral margin of the partition wall I5, the four plies again 30 split to form the flaps 22 and 23. The two outer plies of the partition wall I5, which constitute the inside plies of the flaps, are shorter in length than the two intermediate plies so that the flaps are gradually tapered in thickness and merge smoothly with the interior of the casing I0. Thus, these outer plies may extend one-half the length of the flaps 22 and 23.

Suitable openings 24.are provided in the aps 22 and 23 for the reception ofthe air valve fittings 20 and 2I which may be of any suitableconstruction. In the present instance, they are entirely separate of each other and have bent valve stems as shown in Fig. 1 so that the inner tubes 'are also independent of each other and 45 capable of being used interchangeably in either side of the tire casing Ill. The openings 24 (see Fig. 4) are provided in the form of elongated slots with rounded side edges extending laterally of the casing I0 and permitting the aps 22 and 23 to slide freely relative to the valve stems.

It will be evident that when both inner tubes I8 and I9 are fully inflated, as shown in Fig. 1, the partition wall I5 will be held erect, and the flaps 22 to 23 Will be symmetrically disposed to 55 enclose the tubes and reeniorce same at the sides. In the event that either one of the inner tubes becomes deflated. for example either through apuncture. blowout or leaky valve, the other of the inner tubes will expand to assume the full inner space of the casing il, and thereby will maintain the tire sumciently inflated to avoid any necessity for immediate attention. In expanding, the inner tube presses the partition wall I5 to one side where it and the \col l ylapsed tube serve to close the leak it present in the casing Il. By reason of the slots 24, the flaps 22 and 23 may be partially displaced to accommodate movement of the partition wall I5. The aforesaid adjustment is readily effected without crimping the inner tubes by reason of the smooth intert of all the parts. and the pliancy and shape oi' the partition wall i5 and flaps 22 and 23. The partition wall I5 substantially strengthens the outer casing, and reduces the likelihood o! punctures and blowouts, thus eliminating an element of danger heretofore present in single tube tires.

I claim as my invention:

In a pneumatic tire, in combination, an outer casing having a peripheral tread wall, side walls vwith said casing at the center of said tread wall, two separate interchangeable inner tubes arl0 rangedy respectively in said compartments and having v-alve nttings with stems bent into the plane of the tire, and two lthin, elongated gradually tapered oppositely extending ilexible sideaps joined with the inner peripheral edge ot l5 saidpartition wall and overlapping the adjacent inner portion o! said tubes, said naps extending laterally through approximately one-fourth of the transverse circumference of said casing and having elongated laterally extending slots receiv- 20 ing said stems, said partition wall being formed of the two inner plies of said lining at each side jointed at the center oi said tread wall to form four plies and again split at the inner periphery 2r 0 to form said flaps. 4 l

- LAWRENCE C. MILLS. 

